Structured systems analysis and design methodology SSADM is a set of standards for systems analysis and application design. It uses a formal methodical approach to the analysis and design of information systems.
SSADM can be thought to represent a pinnacle of the rigorous document-led approach to system design, and contrasts with more contemporary agile methods such as DSDM or Scrum. SSADM is one particular implementation and builds on the work of different schools of structured analysis and development methods, such as Peter Checkland's soft systems methodologyLarry Constantine's structured designEdward Yourdon's Yourdon Structured MethodMichael A.
SSADM made mandatory for all new information system developments Version 4 launched The method was repackaged into 15 modules and another 6 modules were added.
Logical data modeling The process of identifying, modeling and documenting the data requirements of the system being designed. The result is a data model containing entities things about which How ssadm work business needs to record informationattributes facts about the entities and relationships associations between the entities.
Data Flow Modeling The process of identifying, modeling and documenting how data moves around an information system. Data Flow Modeling examines processes activities that transform data from one form to anotherdata stores the holding areas for dataexternal entities what sends data into a system or receives data from a systemand data flows routes by which data can flow.
Entity Event Modeling A two-stranded process: Entity Behavior Modeling, identifying, modeling and documenting the events that affect each entity and the sequence or life history in which these events occur, and Event Modeling, designing for each event the process to coordinate entity life histories.
Stages[ edit ] The SSADM method involves the application of a sequence of analysis, documentation and design tasks concerned with the following. Stage 0 — Feasibility study[ edit ] In order to determine whether or not a given project is feasible, there must be some form of investigation into the goals and implications of the project.
For very small scale projects this may not be necessary at all as the scope of the project is easily understood. When a feasibility study is carried out, there are four main areas of consideration: Technical — is the project technically possible?
Financial — can the business afford to carry out the project? Organizational — will the new system be compatible with existing practices?
Ethical — is the impact of the new system socially acceptable? To answer these questions, the feasibility study is effectively a condensed version of a fully blown systems analysis and design. The requirements and users are analyzed to some extent, some business options are drawn up and even some details of the technical implementation.
The product of this stage is a formal feasibility study document. SSADM specifies the sections that the study should contain including any preliminary models that have been constructed and also details of rejected options and the reasons for their rejection.
Stage 1 — Investigation of the current environment[ edit ] The developers of SSADM understood that in almost all cases there is some form of current system even if it is entirely composed of people and paper. Through a combination of interviewing employees, circulating questionnaires, observations and existing documentation, the analyst comes to full understanding of the system as it is at the start of the project.
This serves many purposes. Stage 2 — Business system options[ edit ] Having investigated the current system, the analyst must decide on the overall design of the new system.
To do this, he or she, using the outputs of the previous stage, develops a set of business system options. These are different ways in which the new system could be produced varying from doing nothing to throwing out the old system entirely and building an entirely new one. The analyst may hold a brainstorming session so that as many and various ideas as possible are generated.
The ideas are then collected to options which are presented to the user. The options consider the following: The users and analyst together choose a single business option.
This may be one of the ones already defined or may be a synthesis of different aspects of the existing options. The output of this stage is the single selected business option together with all the outputs of the feasibility stage. Using the requirements developed in stage 1 and working within the framework of the selected business option, the analyst must develop a full logical specification of what the new system must do.
The specification must be free from error, ambiguity and inconsistency.SSADM is one particular implementation and builds on the work of different schools of development methods, some of the key members of which included: We will write a custom essay sample on What is SSADM?
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Introduction - Structured Systems Analysis and Design Methodology (SSADM) SSADM (Structured Systems Analysis And Design Method) is another method dealing with information systems design.
It was developed in the UK by CCT (Central Computer and Telecommunications Agency) in . SSADM is a very comprehensive model, and a characteristic of the method is that projects may use only those elements of SSADM appropriate to the project.
SSADM is supported by . 1.
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